Officers later receive a text message from an anonymous tipster that leads them to a much different conclusion: the boy's 7-year-old cousin accidentally shot him while the two boys were playing with a loaded 9 mm handgun.

Meanwhile, authorities in Douglas County, Colo., thwarted a threatened Columbine-style attack after an anonymous text about a student's "kill list" led them to weapons in the child's home.

After struggling for years with an anti-snitching culture that made witnesses too afraid to come forward, police across the country are getting help from text-a-tip programs that allow people to send anonymous, text messages from their cell phones.

In Boston, the first city to heavily promote texting for crime tips, police have received more than 1,000 tips since the program began two years ago. Police credit text tips for providing them with key leads in at least four high-profile killings, including: the accidental shooting of Liquarry Jefferson by his cousin; an arson fire that killed two children; the shooting of a Boston teenager on her 18th birthday; and the fatal stabbing of a man during a bar fight.

Officer Michael Charbonnier, who oversees the program, said people who live in high-crime neighborhoods are often afraid that if they talk to police, they could be hurt or even killed by gang members, drug dealers or other criminals.

"It's either call 911 or live with the bad guy. And if you call, there could be repercussions," Charbonnier said.

"So when they have this option of texting us _ knowing no one will know who they are _ well, now, people give us license plate numbers, they give us names," he said.

In the past, people feared retaliation for talking to police, but with the texting programs, police never see the tipster's name or telephone number. The text messages are sent to a separate, third-party server, where identifying information is stripped out and they are assigned an encrypted alias before being sent to police.

Texting programs have caught on across the country. The exact number is hard to pinpoint, but Anderson Software, one of the leading providers of technology for text-a-tip programs, has at least 400 law enforcement agencies as clients, including Tucson, Ariz., Savannah, Ga., Hartford, Conn., San Diego, Seattle and Miami.

Company founder Kevin Anderson said text-a-tip programs are rapidly gaining popularity and could soon become as popular as anonymous Web tip programs, which have been around for about five years.

"You want to provide the means of communication people are most comfortable with, and right now, texting is the more comfortable means of communicating for young people," Anderson.

The system allows a tipster to send a text message of up to 160 characters to police, who are then able to send text messages back to the sender to ask follow-up questions. Charbonnier said that because of the two-way communication, Boston police have been able to get the information they need. He said police, who promise tipsters confidentiality and anonymity, have never tried to get a tipster's identity from the third-party company, either by asking for it or through a subpoena.

"The reality is the protection of the tipster is more important than any one case," he said.

Police would not release transcripts of the actual text messages they receive or give specifics on how the tips have led them to suspects, citing the confidentiality they promise tipsters.

Charbonnier said police use the tips as leads and have to corroborate the information given by tipsters, so the tipsters themselves aren't called to court to testify.

Some police departments have heavily promoted the texting service in schools, leading to a flurry of tips about students having drugs and weapons.

In Douglas County, Colo., the sheriff's office got a text message in May from a high school student who said another student had a "kill list." Authorities never found the list but did find weapons in the student's home.

"We did believe it was a credible threat," said Phyllis Harvey, who administers the Text-A-Tip program for the Douglas County Sheriff's Office.

"Did we prevent something? Maybe, maybe not. We don't know if the student was actually going to go through with the threats that he was making, but we would like to hope that we did prevent something."

In Springfield, Mass., the texting program was just days old last month when police received a tip about a crack house. Police raided the house, made eight arrests and shut down the headquarters of a crack distribution ring, said Sgt. John Delaney.

"People don't want to be labeled as a rat," Delaney said. "This is breaking the barriers down."

At the University of Southern California in Los Angeles, campus police have promoted the text-a-tip service as a way to keep rowdy football fans under control during games.

"We get tips like 'three guys who are non-students are being rude and obnoxious behind us,' 'someone is cutting in line at the student gate,'" said Carey Drayton, chief of USC's Department of Public Safety.

"Those are things that could turn into fights. We are trying to stop things before they get too big," he said.

Boston police say the anonymous nature of the text-a-tip service, combined with police foot and bicycle patrols in violent neighborhoods, has helped them build trust with people and put a dent in the anti-snitching attitude that was prevalent for years. Five years ago, some court spectators even wore "Stop Snitchin'" T-shirts to the trial of two men charged in the shooting death of a 10-year-old girl.

"We've made a significant amount of progress in connecting with the community," said Police Commissioner Ed Davis. "That makes a big difference when you're dealing with the whole snitching situation."